A vacuum cleaner is an electrically powered, mechanical appliance utilized for the dry removal of dust and loose dirt from carpets, rugs, fabrics and other surfaces. Vacuum cleaners have been widely used for years in domestic and industrial cleaning applications.
In operation, a pressure drop is utilized to force air entrained with loose dirt and debris into the nozzle of the vacuum cleaner. The dirt and debris laden air is then drawn through a filter bag or dirt cup that traps and retains the dirt. The air is then exhausted by electric fan through an additional filter to remove relatively fine particles such as carbon particles from the brushes of the fan motor. It is this fan that provides the air pressure drop or vacuum that provides the cleaning action. The present invention relates to a vacuum cleaner equipped with a dirt collection vessel and a separate main filter compartment. A dirt detection sensor is provided in the airflow pathway between the dirt collection vessel and the main filter compartment. Indicator lamps indicate when the dirt collection vessel should be emptied and/or the main filter changed.